Coins were first introduced as a method of payment around 2600 years ago (600 BCE) in the Lydian kingdom (around modern-day Turkey).
They brought order to the then-existing unorganized economy, which was based on barter and physical goods such as shells, food, or livestock.
But this order wouldn’t have meant much without standardization and hierarchy of coins.
So, in order for a coin to be considered legitimate, it had to be issued by the governing authority.
And governing authorities of different kingdoms adopted different standards.
The celts (ancient people who lived in parts of Europe & Asia), for example, engraved their money with symbols, and pictures of important kings.
Romans engraved the face of the ‘current’ emperor of Rome and ‘heads’ was used to describe this side of the coin.
‘Tails’ comes because the tail end of something is at the opposite of the head – it is a logical conclusion and doesn’t mean anything special.
This practice continues in many countries today and even countries that do not have coins with the head of a person call sides of their coins ‘heads’ and ‘tails’.
For coins that don’t have the face of a person, the side with a large-scale image is called the obverse (bearing the principal design) and, therefore, ‘heads’.
If the coins of a country don’t have any large scale image, the side that is more typical of a wide range of coins is generally called ‘heads’.
For example, most coins in India have the State Emblem (4 lions mounted on a circular base) and, therefore, this side is called ‘heads’.
